JP2018062173A - Laminate film having excellent lubricity and blocking resistance, and packaging material and package prepared therewith - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminate film that has excellent heat sealability without increasing the types of additives or the amount of lubricants, and has excellent lubricity and blocking resistance in a processing step, and a packaging material and a package prepared with the laminate film.SOLUTION: A laminate film has a thermoplastic resin as the main resin, and has at least a first layer (4) and a second layer (5), where the first layer contains fatty acid amide as an organic lubricant and also contains at least one of organic particles or inorganic particles; the first layer has an average crystallinity of 30% or more to 50% or less; the first layer has a thickness of 5 μm or more to 30 μm or less; the second layer has an average crystallinity of 40% or more to 60% or less, which is higher than the average crystallinity of the first layer; the second layer has a thickness of 30 μm or more to 100 μm or less.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a laminated film suitable for a packaging material having various physical properties such as low-temperature heat-sealing property, tearing property, and rigidity, slipperiness, and blocking resistance, and a packaging material and a packaging body using the same.

  The packaging material is used for packaging bags for packaging food products, pharmaceuticals, and the like, and the contents of the packaging bags have various states such as liquid, powder, paste, and solid. For example, plastic film packages using films of polyethylene, polypropylene, ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, polyamide, polyester, etc. are often used.

  Such a packaging bag is required to have characteristics such as filling suitability at the time of filling contents, absence of damage to the bag when an external force is applied to the packaging material, air tightness, and unsealing property when opening the packaging bag. In order to obtain such a packaging bag, the packaging material has good impact resistance, low-temperature heat sealability, tearability, rigidity, barrier properties, etc., as well as good slipping, blocking resistance, and winding properties in the processing process. Such characteristics are also required.

  In order to improve the slipperiness of the packaging material, it is necessary to change the surface free energy of the packaging material. For example, a method to reduce the contact area by providing a concavo-convex shape on the surface of the packaging material, a method to add a slip agent that can reduce the surface free energy, an increase in the surface area at the time of contact to reduce energy loss when the material is deformed In order to avoid this, it is possible to use a material having high rigidity.

  For example, in patent document 1, the countermeasure of adding uneven | corrugated shape to the plastic film of a sealing layer is taken. By adding a concavo-convex shape to the plastic film, the contact area is reduced to increase the slipperiness, and the bending when the package is formed is suppressed, thereby improving the self-supporting property of the film.

  Moreover, in patent document 2, in order to improve the tearability of the whole package, about the laminated | multilayer film which used the biaxially-stretched nylon film as a base material, combining sealing layer with a material density higher than a laminated layer is described. Yes.

Japanese Patent No. 4871456 Japanese Patent Laid-Open No. 10-337828

  However, when a concavo-convex shape is imparted to the surface of the seal layer as in Patent Document 1, the concavo-convex shape is deformed by the pressure at the time of contact between the films unless a sufficiently rigid material is used. As a result, the contact area between the seal layers increases, so that improvement in slipperiness cannot be expected. Furthermore, it is necessary to pass through a press plate process to give the uneven shape, and there are problems such as an increase in manufacturing cost due to a decrease in yield.

  Further, when a material having high rigidity is used for the seal layer as in Patent Document 2, the slip property is improved, but there is a problem that heat sealability at low temperature cannot be expected and high-speed filling suitability is not sufficient.

  Furthermore, when the slip property is improved by adding a slip agent to the packaging material, it is common to add a slip agent of about 200 to 400 ppm. These slip agents can be added to the resin and exhibit slip characteristics due to the bleed-out phenomenon that precipitates on the film surface, but the slip properties change depending on storage conditions and product processing conditions. In addition, the lubricant is transferred to the back surface or another film in contact with the bleed-out surface of the lubricant, and the sliding property of the transferred surface is also changed. Therefore, in order to obtain stable lubricity, it is desired that the amount of lubricant is smaller.

  Therefore, the present invention is a laminated film suitable for a packaging material having good heat-sealability without increasing the kind of additive and the amount of lubricant, and having good lubricity and blocking resistance in processing steps, and An object of the present invention is to provide a packaging material and a package using the laminated film.

In order to solve the above problems, one of the representative films of the present invention is
A laminated film comprising a thermoplastic resin as a main resin, having at least a first layer and a second layer,
The first layer contains a fatty acid amide,
Contains at least one of organic particles or inorganic particles,
The average crystallinity of the first layer is 30% to 50%, and the thickness of the first layer is 5 μm to 30 μm,
The average crystallinity of the second layer is 40% to 60%, which is higher than the average crystallinity of the first layer, and the thickness of the second layer is 30 μm to 100 μm. It is a laminated film.
Moreover, the typical packaging material of this invention has laminated | stacked the base material layer on the said laminated | multilayer film.
Furthermore, a typical package of the present invention uses the above packaging material.

  The present invention provides various physical properties such as low-temperature heat-sealability, tearability, and rigidity by providing an appropriate average crystallinity gradient for each layer of a laminated film containing a thermoplastic resin as a main resin. Can have good lubricity and blocking resistance without increasing the kind of additive and the amount of lubricant.

It is the perspective view which showed an example of embodiment of this invention. It is the perspective view which showed an example of embodiment of this invention. It is the perspective view which showed an example of embodiment of this invention. It is the figure which showed the outline | summary of the organic lubricant presence amount measuring method of this invention. It is sectional drawing of the standing pouch using the sealant film for packaging materials of this invention. It is a schematic diagram which shows the manufacturing process of the standing pouch using the sealant film for packaging materials of this invention.

  Below, embodiment of the film for packaging materials of this invention is described. Each figure is a schematic diagram, and the size, shape, and the like of each part are appropriately exaggerated for easy understanding. For the sake of simplicity, the same reference numerals are given to corresponding parts in the drawings.

  As shown in FIG. 1, the laminated film 1 includes at least a first layer 4 on one surface of a second layer 5 of thermoplastic resin.

Here, there is a difference in average crystallinity between the thermoplastic resin used for the first layer 4 and the thermoplastic resin used for the second layer 5.
Regarding the average crystallinity, the first layer 4 is 30% to 50% and the second layer 5 is 40% to 60%, and at least the average crystallinity of the second layer 5 is The average crystallinity of the first layer 4 is preferably higher.
At this time, the average crystallinity is all measured in the MD direction of the thermoplastic resin layer. The measurement method may be to measure each surface of the film using Raman spectroscopy, or each sample piece cut so that only each layer can be taken out, or from the film surface to the depth direction Measurements may be made layer by layer with a focus. Needless to say, the cross section of the film may be measured after the cross section of the film. As for the measurement method, there is no problem even if measurement is performed with an apparatus such as FT-IR.

  Furthermore, the thickness of the first layer 4 is preferably 5 μm to 30 μm, and the thickness of the second layer is preferably 30 μm to 100 μm.

When the average crystallinity of the first layer 4 is 50% or more or the thickness is 5 μm or less, the heat sealability at low temperature is lowered, and the average crystallinity of the first layer 4 is 30%. Below, or when the thickness is 30 μm or more, there arises a problem that tearability and rigidity are lowered.
On the other hand, when the average crystallinity of the second layer 5 is 40% or less, or when the thickness is 30 μm or less, it causes a decrease in tearability and rigidity, and the average crystallinity of the second layer 5 is 60% or more, or When the thickness is 100 μm or more, there is no problem in heat sealability, tearability, and rigidity, but there is a problem that the impact resistance is reduced or the cost is increased because the film thickness is more than necessary.

  That is, by making an appropriate difference in average crystal as in the present invention, the laminated film 1 can appropriately maintain physical properties such as low temperature heat sealability, tearability, and rigidity suitable for packaging materials. .

  Below, the detail of each structure in this embodiment is demonstrated.

(Laminated film)
The thermoplastic resin that is the material of the laminated film 1 preferably has good workability such as having appropriate flexibility and, for example, suitability for processing by an extruder. Such materials include, for example, low density polyethylene (LDPE), linear low density polyethylene (LLDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE), and homopolymers, random copolymers, and block copolymers. Polypropylene, ethylene vinyl acetate copolymer obtained by copolymerizing the olefin and vinyl acetate, ethylene-methyl acrylate copolymer (EMA) obtained by modifying the side chain of olefin, ethylene-ethyl acrylate copolymer (EEA), An ethylene-butyl acrylate copolymer (EBA), an ethylene-methacrylic acid copolymer (EMAA), etc. are mentioned. These materials may be used alone, or a plurality of these materials may be used in combination.

The laminated film 1 for packaging materials is mainly composed of polyethylene or a derivative thereof, and the average density of the first layer 4 is 0.910 g / cm ^{3 to} 0.930 g / cm ³ , and the second layer 5 is more desirably 0.920 g / cm ^{3 to} 0.940 g / cm ³ and higher than the average density of the first layer 4.
Here, “mainly” means that the resin used for the laminated film 1 is 70% or more by weight. The average density is measured by a measuring method based on JIS K7112: 1999 or a measuring method comparable to this.

  In general, impact resistance and heat sealability can be improved by using a low-density resin for the thermoplastic resin, but on the other hand, rigidity, tearability, slipperiness during processing, and blocking resistance deteriorate. End up. However, the laminated film 1 has a two-layer structure as shown in FIG. 2, the first layer 4 is a low-density resin, and the second layer 5 is a medium to high-density resin, so that the impact resistance and the heat seal property are improved. Bending rigidity and tearability can be improved while maintaining good conditions.

  Both the first layer 4 and the second layer 5 are preferably a mixture of linear low density polyethylene (LLDPE) and low density polyethylene (LDPE). By mixing LDPE with LLDPE, the above-mentioned various physical properties can be made compatible with workability such as neck-in. More preferably, the weight ratio of LLDPE: LDPE is mixed at a ratio of 99: 1 to 70:30.

  Further, for example, as shown in FIG. 2, a multilayer structure in which a plurality of layers are stacked and stacked in two or more layers to complement desired physical properties may be used. As an example of a multilayer structure, in order to further increase the rigidity of the laminated film 1, a resin layer having a higher density than the resin used for the first layer 4 and the second layer 5 is used for the third layer 44 and the fourth layer 55. Alternatively, a resin layer having a density similar to that of the first layer 4 may be used for the third layer 44 in order to suppress curling due to heat shrinkage of the packaging material film.

(Anti-blocking (AB) agent)
In order to obtain good slipperiness and blocking resistance in the processing step, the first layer 4 has an organic system different from the thermoplastic resin as an anti-blocking agent (hereinafter sometimes referred to as “AB agent”). It is preferable that at least one kind of particles or inorganic particles is contained in an amount of 6000 ppm to 50000 ppm.
At this time, the organic particles or the inorganic particles may directly form a convex shape, or the convex shape may be formed by covering the periphery of the particles with a thermoplastic resin. Of course, organic particles or inorganic particles may be substantially embedded in the thermoplastic resin, and only a part of the particles may protrude.

  Furthermore, the organic particles or the inorganic particles contained in the first layer 4 have an average particle diameter of 3 μm to 15 μm, and the arithmetic average roughness Ra (JISB0601-) of the surface 2 of the first layer 4 formed with this convex shape. 2001) is 0.5 μm to 2.0 μm, it is possible to obtain good slipping and blocking resistance.

  The second layer 5 contains 1000 ppm to 10,000 ppm of at least one kind of organic particles or inorganic particles having an average particle diameter of 2 μm to 8 μm.

  Examples of organic particles or inorganic particles include acrylic particles, styrene particles, styrene acrylic particles and cross-linked products thereof, polyurethane particles, polyester particles, silicon particles, fluorine particles, copolymers thereof, zeolites, and the like. , Pyrophyllite, talc, smectite, vermiculite, mica, chlorite, kaolin mineral, sepiolite and other clay compound particles, silica, titanium oxide, alumina, silica alumina, zirconia, zinc oxide, strontium oxide, aluminum hydroxide, strontium carbonate Strontium chloride, strontium sulfate, strontium nitrate, strontium hydroxide, glass particles and the like.

For organic particles, it is easy to select an appropriate particle size, but care must be taken because they may be thermally decomposed. In the case of organic fine particles, those whose weight change at a temperature of 300 ° C. is 10% or less are preferable. In the case of a film for a packaging material, since it involves a heat forming process, if the weight change is large, there is a possibility that problems such as generation of odor or burn due to decomposition and promotion of deterioration of the apparatus may occur.
Furthermore, it is preferable to use hard spherical organic particles or inorganic particles as compared with thermoplastic resins, and to produce a convex shape using such particles to improve effective slipperiness. In addition, the deformation of the convex shape due to the frictional force can be suppressed, and an appropriate frictional force can be maintained.

(Lubricant)
In order to obtain more appropriate lubricity, the thermoplastic resin preferably contains an organic lubricant, but the amount of the organic lubricant present on the convex surface 2 is preferably 5 mg / m ² or less. . More preferably, it is 3 mg / m ² or less.

Although the situation varies depending on the type of thermoplastic resin, the presence / absence or type of adhesive, temperature conditions, and the like, in general, the lubricant tends to move to the film surface due to changes over time after film formation or after temperature change. That is, a bleed-out phenomenon occurs. Therefore, the slipperiness of the film changes depending on storage conditions and product processing conditions. Further, when the back surface of the same film or another film comes into contact with the bleed-out surface of the lubricant, the lubricant is transferred to the back surface or another film, and the lubricity of the transferred surface is also changed. Therefore, as described above, it is desired that the amount of the lubricant is as small as possible in order to obtain stable lubricity.
In general, a large amount of organic lubricant is added to make it slippery. However, in the present invention, by adding an appropriate convex shape, it is possible to keep the slipperiness moderately, so that it exists on the surface 2. The amount of organic lubricant used is as small as 5 mg / m ² or less. Thereby, it is possible to obtain a laminated film 1 suitable for a packaging material that does not change under appropriate slipperiness under any conditions. As the addition amount, about 30 ppm to 150 ppm is sufficient for the laminated film.

The evaluation of the amount of the organic lubricant present on the surface 2 is performed, for example, by a method as shown in FIG. First, an organic lubricant surface extraction jig 241 is fixed to the surface 2, and an organic solvent 242 into which the organic lubricant is dissolved is injected therein. When several seconds to several minutes have passed after the injection, the organic solvent 242 is taken out, and the taken out organic solvent is evaluated by an apparatus such as a gas chromatograph or FT-IR. Since the organic lubricant present on the surface 2 is dissolved in the organic solvent, the amount of the organic lubricant present on the surface 2 can be measured by evaluating and analyzing the organic solvent 242.
The organic lubricant surface extraction jig 241 is a cylinder for keeping the organic solvent 242. In order to prevent the organic solvent 242 from evaporating, it is preferable that the upper portion has no opening. Examples of the organic solvent 242 include chloroform, acetone, ethanol, methanol, and the like.
Further, the method for measuring the amount of the organic lubricant present on the surface 2 is not limited to the above method, and measurement is possible if the film surface can be washed with the organic solvent 242. For example, the amount of organic lubricant present on the surface 2 can be measured by a method of immersing the film in the organic solvent 242 for several seconds to several minutes.

  Examples of organic lubricants include, for example, sucrose fatty acid esters, glycerin fatty acid esters, synthetic resin systems such as hydrocarbons such as liquid paraffin, paraffin wax, and synthetic polyethylene wax, fatty acid systems such as stearic acid, behenic acid, stearyl alcohol, Examples thereof include fatty acid amides such as stearic acid amide, oleic acid amide, erucic acid amide, methylene bis stearic acid amide, ethylene bis stearic acid amide, and ethylene bis oleic acid amide.

  Of these, fatty acid amides having a molecular weight of 250 to 350 such as stearic acid amide, oleic acid amide, erucic acid amide, and behenic acid amide are suitable. This is because these organic lubricants have a fast bleed-out to the film surface and can exert an effect immediately after molding.

  The laminated film 1 may contain other various additives. For example, an antioxidant or the like for imparting processing stability can be appropriately added.

(Production method)
The method for producing the laminated film 1 suitable for the packaging material of the present invention is not particularly limited, and a known method can be used. For example, the laminated film 1 can be produced by adding organic particles or inorganic particles and an organic lubricant to a thermoplastic resin and forming a film using an extruder. As a film forming method, it is possible to form a film by a known method such as an air chamber, an air knife, a vacuum chamber, or a method combining a plurality of them.

(Packaging material)
As shown in FIG. 3, on the back surface 3 opposite to the front surface 2 which functions as a heat seal layer, a base layer 7 and further a functional layer 8 such as a printing layer or a barrier layer is provided on the laminated film 1. By forming, the packaging material 6 having the effects of the present invention can be obtained. In FIG. 4, a three-layer configuration of the base material layer 7, the functional layer 8, and the laminated film 1 is shown, but not limited thereto, a two-layer configuration of the base material layer 7 and the laminated film 1, and a multilayer of four or more layers It is good also as a structure.

(Laminated film)
When the laminated film 1 for a packaging material is processed into a package, the average crystallinity of the entire laminated film 1 is increased. This is because the thermoplastic resin used for the laminated film 1 has a characteristic of being softened again by being heated even after film formation.
Specifically, in the processing step of the packaging material 6, it is common to use an organic adhesive when laminating the laminated film 1, the base material layer 7 and the functional layer 8. At this time, in order to improve adhesive strength, it is known to pass through a heating process called aging that is allowed to stand for several days in an environment of about 30 ° C. to 80 ° C. Since the heat given during this aging is higher than the glass transition temperature (Tg) of the thermoplastic resin, the thermoplastic resin used for the laminated film 1 re-softens and the molecular chain motion becomes active, Induces recrystallization. Therefore, even if the physical properties at the time of forming the laminated film 1, for example, good heat-sealing properties are exhibited, the crystallinity increases at the time of the packaging material 6, and good results may not be obtained. is there.
Based on such knowledge, in the present invention, even when the laminated film 1 is subjected to a heating step of about 30 ° C. to 80 ° C. after film formation, the average crystallinity is 35% to 70%. It is characterized by a range.
In general, the resin density of the raw material used for film processing and the crystallinity of the molded film are said to have a positive correlation. In the present invention, however, the correlation between the resin density and the crystallinity is the packaging material 6. It is based on the new knowledge that the validity is lost at the time of processing.

  From these facts, when processing the laminated film 1 into the packaging material 6, the generally known correlation between the raw material resin density and the degree of crystallinity of the molded film is not appropriate, and in the present invention, the packaging material 6 is good. In order to maintain proper physical properties, the material design takes into account the increase in crystallinity during processing into a package.

(Base material layer)
The base material layer 7 is a layer that functions as a support for the packaging material 6, and generally a film mainly made of plastic is used, but the use conditions such as the type of contents and the presence or absence of heat treatment after filling are used. Thus, the material constituting the base material layer is appropriately selected. As a material for the base material layer 7, for example, polyethylene, polypropylene, polyethylene terephthalate, nylon or the like may be used other than a film mainly made of plastic, and is not particularly limited.
Further, it may be a single layer made of one of the above materials, or may be a layer in which a plurality of the above materials are combined by stacking such single layers.

(Functional layer)
Examples of the functional layer 8 include a printing layer and a barrier layer. The barrier layer is a layer having a function of improving the barrier property for protecting the packaging material from a gas such as oxygen contained in the air, water vapor, enclosed contents, and the like. Examples of the material include EVOH and aluminum. These metals can be used as appropriate.

(Packaging body)
By using the packaging material 6 of the present invention, the peripheral edges of the laminated films 1 facing each other are welded together by heat sealing or the like, thereby obtaining a packaging body having the above-described effects of the present invention.

  Examples of the package of the present invention include a standing pouch, a packaging bag, a pouch with a stopper, a lami tube, a back-in box, and the like, but can be used for various other purposes.

(Standing pouch)
As an example of the package, a structure and a manufacturing method when the packaging material 6 of the present invention is employed in a standing pouch will be described with reference to FIGS. A standing pouch is a kind of container that can store liquids, powders, and solids, such as toiletries such as liquid detergents, softeners, shampoos, and rinses, and foods such as edible oil, instant coffee, and sake. In addition to the bag-making method similar to the above-mentioned package, the sealant film is used as a bottom tape, and is inserted between the main body surface and the back surface of the main body to seal the periphery, so that it can easily stand on its own. FIG. 5 is a cross-sectional view of the standing pouch 12, and FIG. 6 is a schematic view showing a state during web conveyance before the standing pouch 12 is formed.

  Hereinafter, the standing pouch 12 obtained by the present invention will be described in detail. As shown in FIG. 5, the standing pouch 12 has a pouch surface 13 and a pouch back surface 14 by bending the laminated film 1 of the packaging material 6 of the present invention inside. At that time, the peripheral seal portion composed of the left and right side seal portions 22 and the bottom seal portion 23 indicated by hatching in FIG. 9 is heat sealed to form a package.

  Furthermore, the bottom tape 20 can be formed separately and inserted between the pouch front surface 13 and the pouch back surface 14 to seal the periphery, thereby providing self-supporting properties.

  In addition, a pour nozzle 16 for pouring the contents is formed on the upper portion of the standing pouch 12 (on the side opposite to the bottom tape 20) by a pouch surface 13, a pouch back surface 14, and a pour nozzle seal portion 24. . The extraction nozzle seal portion 24 is a seal portion that is provided continuously to the side seal portion 22, and is provided below the extraction nozzle 16.

  The dispensing nozzle 16 is formed with a dispensing nozzle tip seal portion 25 whose tip is heat-sealed, and functions as an opening knob 18 separated and formed by an opening cut line 17 provided on the dispensing nozzle seal portion 24. To do. That is, the user can form the spout (not shown) by holding the opening knob 18 and cutting along the pre-formed half cut line 19. Note that the present invention is not limited to this method, and a cap with a cap formed of resin or the like may be separately provided, and the function of the extraction port may be provided by opening and closing the plug.

  The half-cut line 19 is provided on each of the pouch surface 13 and the pouch back surface 14. As a method for forming a half-cut line, a method of forming with a blade or a method of forming by laser processing is generally used, but the method by laser processing is preferable because a uniform and stable cut can be formed. As the type of laser, a carbon dioxide laser is more preferable.

  As an example of the manufacturing method of the standing pouch 12, as shown in FIG. 10, the packaging material 6 having a width slightly more than twice the height when the standing pouch 12 is self-supported is unrolled into a web shape and half-cut. Line 19 is formed. Thereafter, the laminated body is bent at the bent portion ridge line 21 to form the pouch surface 13 and the pouch back surface 14, and the bottom tape 20 is inserted to perform heat sealing of the peripheral portion, and punching into a predetermined shape. Can be configured.

  In addition, other features such as forming a continuous embossed portion 26 from the pouch surface 13 to the pouch back surface 14 via the bent portion ridge line 21 may be provided in the dispensing nozzle 16. . That is, by using the packaging material 6 of the present invention, the standing pouch 12 having the above-described effects can be obtained.

  As mentioned above, although embodiment of this invention was illustrated, this invention is not limited to the said embodiment, Unless it deviates from the technical idea of this embodiment, it considers the use as a packaging material, and is requested | required. Needless to say, other layers and structures can be arbitrarily formed for the purpose of improving other physical properties such as rigidity, strength, impact property and the like.

  Examples of the present invention will be described in detail below, but the present invention is not limited to the following examples.

Example 1
The laminated film 1 is a two-layer laminated film, and as the thermoplastic resin of the first layer 4, a linear low density polyethylene resin (density 0.913 g / cm ³ , MFR 3.8) and a low density polyethylene resin (density 0.924 g). / Cm ³ , MFR 1.0) was blended at a ratio of 80:20, and 35000 ppm of organic particles (acrylic crosslinked product) having an average particle diameter of 10 μm were added as an AB agent, and 100 ppm of erucamide was added as a lubricant. Further, as the thermoplastic resin of the second layer 5, a linear low density polyethylene resin (density 0.931 g / cm ³ , MFR 3.2) and a low density polyethylene resin (density 0.924 g / cm ³ , MFR 1.0). Were blended at a ratio of 80:20, and inorganic particles (zeolite) having an average particle size of 5 μm were added at 3000 ppm, and erucamide was added at 100 ppm as a lubricant. The first layer 4 and the second layer 5 are each heated and melted at 260 ° C. by a single screw co-extruder, and the thickness of the first layer 4 is 15 μm and the thickness of the second layer 5 is 85 μm by T-die casting. A laminated film 1 having a total thickness of 100 μm was formed.

(Example 2)
The density of the main resin LLDPE of the first layer 4 was changed to 0.920 g / cm ³ , and a film for packaging material was produced in the same manner as in Example 1 except for the other configurations.

(Example 3)
The density of the main resin LLDPE of the second layer 5 was changed to 0.920 g / cm ³ , and a film for packaging material was produced in the same manner as in Example 1 except for the other configurations.

Example 4
The density of the main resin LLDPE of the second layer 5 was changed to 0.940 g / cm ³ , and the other structures were made in the same manner as in Example 1 to produce a packaging material film.

(Example 5)
The thickness of the first layer 4 was changed to 5 μm, and other configurations were made in the same manner as in Example 1 to produce a packaging material film.

(Example 6)
The thickness of the first layer 4 was changed to 30 μm, and the other structures were made in the same manner as in Example 1 to produce a packaging material film.

(Example 7)
A weight ratio of the first layer 4 main resins LLDPE and LDPE was changed to LLDPE: LDPE = 90: 10, and other configurations were made in the same manner as in Example 1 to produce a film for packaging material.

(Example 8)
A weight ratio between the main resins LLDPE and LDPE of the second layer 5 was changed so that LLDPE: LDPE = 90: 10, and other configurations were made in the same manner as in Example 1 to produce a packaging material film.

Example 9
The weight ratio of the main resin LLDPE and LDPE of the first layer 4 was changed to LLDPE: LDPE = 90: 10, and the weight ratio of the main resin LLDPE and LDPE of the second layer 5 was changed to LLDPE: LDPE = 90: 10, Other configurations were the same as in Example 1 to produce a packaging material film.

(Example 10)
The AB agent added to the first layer 4 was changed to 35000 ppm of inorganic particles having the same average size, and other configurations were made in the same manner as in Example 1 to produce a film for packaging material.

(Example 11)
A film for packaging material was produced in the same manner as in Example 1 except that the amount of the organic agent added to the first layer 4 was changed to 10,000 ppm.

(Example 12)
The lubricant to be added to the first layer 4 was changed to 150 ppm, and other structures were made in the same manner as in Example 1 to produce a film for packaging material.

(Example 13)
A weight ratio of the first layer 4 main resins LLDPE and LDPE was changed to LLDPE: LDPE = 95: 5.

(Example 14)
A weight ratio of the first layer 4 main resins LLDPE and LDPE was changed to LLDPE: LDPE = 5: 95, and other configurations were made in the same manner as in Example 1 to produce a film for packaging material.

(Example 15)
A weight ratio between the main resins LLDPE and LDPE of the second layer 5 was changed to LLDPE: LDPE = 95: 5, and other configurations were made in the same manner as in Example 1 to produce a packaging material film.

(Example 16)
A weight ratio between the main resins LLDPE and LDPE of the second layer 5 was changed to LLDPE: LDPE = 5: 95, and other configurations were made in the same manner as in Example 1 to produce a packaging material film.

(Comparative Example 1)
The density of the main resin LLDPE of the second layer 5 was changed to 0.913 g / cm ³ , and the other structures were made in the same manner as in Example 1 to produce a packaging material film.

(Comparative Example 2)
The main layer resin density of the first layer 4 was changed to 0.931 g / cm ³ , and the other components were produced in the same manner as in Example 1 to produce a packaging material film.

(Comparative Example 3)
The thickness of the first layer 4 was changed to be 0 μm, and other configurations were made in the same manner as in Example 1 to produce a packaging material film.

(Comparative Example 4)
The thickness of the first layer 4 was changed so as to be 50 μm, and other configurations were made in the same manner as in Example 1 to produce a packaging material film.

(Comparative Example 5)
The thickness of the first layer 4 was changed to be 100 μm, and other configurations were made in the same manner as in Example 1 to produce a packaging material film.

(Comparative Example 6)
A film for a packaging material was produced in the same manner as in Example 1 except that the organic particles of the AB agent added to the first layer 4 were changed to 0 ppm.

(Comparative Example 7)
A film for packaging material was produced in the same manner as in Example 1 except that the amount of the organic agent added to the first layer 4 was changed to 100000 ppm.

(Comparative Example 8)
The erucic amide of the lubricant added to the first layer 4 was changed to 0 ppm, and other structures were made in the same manner as in Example 1 to produce a packaging material film.

(Comparative Example 9)
The erucic amide of the lubricant added to the first layer 4 was changed to 500 ppm, and the other components were produced in the same manner as in Example 1 to produce a film for packaging material.

(Evaluation experiment)
Bending rigidity evaluation experiment, tearability evaluation experiment, heat seal evaluation experiment, impact resistance evaluation as evaluation of performance required for various packaging materials with respect to the laminated film 1 of the thermoplastic resin obtained in each example and each comparative example Experiments, lubricity evaluation experiments, lubricant surface abundance evaluation experiments, surface roughness evaluation experiments, and blocking resistance evaluation experiments were performed. Furthermore, the heat sealability evaluation when this was processed into the packaging material 6 was also implemented.

The average crystallinity of the produced film is evaluated using microscopic laser Raman. At this time, the case where the crystallinity falls within the range of 30% to 42% is low, the case where the crystallinity falls within the range of 43% to 49%, and the case where it falls within the range of 50% to 70% or higher. The measuring method is as follows.
Using a nanophoton microscopic laser Raman spectrometer (RAMAN touch), each film was measured three times in the MD direction to evaluate the average crystallinity of each layer. This time, since polyethylene was targeted, the Raman shift observed by superimposing the skeletal vibration of the crystal part and the amorphous part is based on the peak area of 1300 / cm, and the skeleton vibration of the crystal part is observed relative thereto. Is the average crystallinity by calculating the ratio of the peak area around 1130 / cm.

[Execution evaluation experiment]
(Film formability evaluation)
Film formability evaluation measured the width | variety of the laminated | multilayer film 1 shape | molded aiming at thickness of 100 micrometers, and evaluated formability by comparing T-die width | variety. Specifically, when the T-die width and the film width are the same, when 100%, the film width is 75% or more, ◯, 70% or more, and the others are x.

(Bending stiffness evaluation experiment)
The bending stiffness was evaluated by using a loop stiffness tester manufactured by Toyo Seiki Seisakusho, with a compression speed of 3.3 mm / sec, a sample width of 15 mm, and a loop length of 85 mm. At this time, the measurement was carried out three times in the MD direction. As a bending rigidity evaluation when measured, 15 g or more was evaluated as “◯”, 10 g or more as “Δ”, and other than “×”.

(Tearability evaluation test)
In tearing evaluation, it measured using the tear method by Elmendorf described in JISK7128-2. At this time, it measured 3 times with respect to MD direction of a film, respectively. As tearability evaluation, 5N or less was evaluated as ◯, 10N or less was evaluated as Δ, and the others were evaluated as ×.

(Heat sealability evaluation experiment)
The heat sealability was evaluated using a tester industry heat sealer (model TP-701-B) with a seal pressure of 0.2 MPa, a seal time of 1 second, a seal width of 10 mm, and a seal temperature of 100 ° C. to 10 ° C. Then, the surfaces having the convex shape of the laminated film 1 were overlapped and sealed. Cut the sealed film into 15 mm width x 100 mm, measure the T-shaped peel strength using a tensile tester (model number AGS-500NX) manufactured by Shimadzu Corporation with a distance between chucks of 50 mm and a pulling speed of 300 mm / min. Strength. As a result, the lowest temperature at which the seal strength was 10 N or higher was determined as the heat seal expression temperature. At this time, 120 ° C. or lower was evaluated as “◯”, 140 ° C. or lower as “Δ”, and the other temperatures as “×”.
About this, experiment was implemented about two of the film for packaging materials, and a packaging material.

(Impact resistance evaluation experiment)
In the measurement of impact resistance, an impact test method by a JISK7124-1 free fall dart method and a first part staircase method A method was performed using a tester industry dart impact tester (model number IM-302). At this time, a 50% fracture weight of 350 g or more was evaluated as “◯”, 250 g or more as “Δ”, and other than that as “x”.

(Lubricity evaluation experiment)
For the evaluation of lubricity, the coefficient of static friction was evaluated by a tilt angle measuring method using a sliding tilt angle measuring device manufactured by Toyo Seiki Seisakusho. The films described in Examples and Comparative Examples were cut into a width of 100 mm × a length of 240 mm and a width of 30 mm × a length of 80 mm. A film cut into a width of 100 mm × a length of 240 mm is fixed so that there is no bending in the static friction coefficient measuring device, and a film cut into a width of 30 mm × a length of 80 mm is 30 mm wide × 40 mm long × 30 mm high and has a weight of 197 g. It fixed so that all the measurement surfaces might be coat | covered with respect to the weight. Measurements were made three times, and those with a static friction coefficient exceeding 1.2 cannot be measured, and those with a coefficient of 0.1 or less are indicated with x in the table. Moreover, the thing with the static friction coefficient in the range of 0.1-1.2 was set as (triangle | delta), and the thing in the range of 0.15-0.90 was set as (circle) among them.

(Lubricant surface abundance evaluation experiment)
As shown in FIG. 4, an organic lubricant surface extraction jig 241 was fixed to the surface 2, and chloroform was injected as an organic solvent 242 into the jig. One minute after the injection, chloroform was taken out, and the amount of organic lubricant present on the surface 2 was measured with a gas chromatograph / hydrogen flame ionization detector manufactured by Agilent Technologies. The column used HP-5MS. In addition, measurement is performed using chloroform solutions in which several erucic acid amides having different concentrations are dissolved in advance as a standard solution, and a calibration curve of peak area and concentration is drawn to convert the amount into surface abundance.
At this time, when the amount of lubricant present on the surface 2 was 5 mg / m ² , it was evaluated as ◯, and when it was more than that, it was evaluated as x.

(Surface roughness evaluation experiment)
In the surface roughness evaluation experiment, the arithmetic average roughness Ra of the surface 2 was evaluated with reference to JISB0601-2001 using a Keyence laser microscope (model number VK-X200). At this time, the value of Ra falls within the range of 0.3 μm to 2.0 μm, Δ among them, where Ra falls within the range of 0.5 μm to 1.5 μm, ○, and other than that .

(Blocking resistance evaluation experiment)
Evaluation of blocking resistance was performed by visually evaluating whether or not blocking was performed after 10 layers of the laminated film 1 were stacked and held for 2 days under a load of 0.3 MPa using a compression tester manufactured by Tester Sangyo. . What was blocking was set as x, and what was not done was set as o.

(Evaluation of overall average crystallinity when processed into packaging materials)
The overall average crystallinity evaluation was performed in the same manner as the average crystallinity evaluation for each layer.
At this time, the case where the overall average crystallinity falls within the range of 35% to 70% was marked with ◯, and the others were marked with x.

(Comprehensive evaluation)
As a comprehensive judgment, a circle satisfying all the following four cases was evaluated as “◯”. That is, the average crystallinity evaluation is ◯, the film formability is ◯, the heat sealability evaluation is Δ or more, and the static friction coefficient evaluation is Δ or more. When even one of these evaluation items was x, the comprehensive judgment was also x.
In addition, in the result of the overall evaluation being ◯, when there are four or more Δ including other evaluation items, this effect is obtained, but the overall evaluation is set as Δ because it is somewhat inferior.

(Evaluation results)
Tables 1 to 5 show the results of the above-described evaluation tests performed on each example and each comparative example. Tables 2, 3, 4, and 5 are rearranged so that the evaluation results in Table 1 can be easily compared. That is, Table 2 shows what changed the main resin density of the first layer 4 and the second layer 5, and Table 3 shows what changed the thickness of the first layer 4 and the second layer 5. Table 4 shows the case where the mixing ratio of LLDPE: LDPE of the first layer 4 and the second layer 5 is changed. Table 5 shows the type and amount of the AB agent in the first layer 4, and the first The amount of the lubricant added to the layer 4 is changed.

From Table 2, when the main resin density of the first layer 4 is equal to or higher than that of the second layer 5, the average crystallinity tends to increase, and the heat sealability and tearability tend to be affected. I understand. Here, if the main resin density of the first layer 4 is lower than that of the second layer 5, the effect of the present invention can be obtained, and the main resin density of the first layer 4 is 0.920 g / cm ³ or less, the second layer It can be seen that the evaluation result is most favorable when the main resin density of 5 is 0.930 g / cm ³ or more.

  From Table 3, when the layer thickness of the 1st layer 4 is 0 micrometer, it becomes impossible to ensure low temperature heat-sealing property, On the other hand, when the thickness of the 2nd layer 5 is 0 micrometer, the thickness of the 1st layer 4 and the 2nd layer 5 is further When the ratio is 1: 1, it can be seen that the tearability and bending rigidity tend to be inferior. Here, when the thickness of the first layer 4 is in the range of 5 μm to 30 μm and the thickness of the second layer 5 is in the range of 70 μm to 95 μm, the effect of the present invention can be obtained, and the physical property results evaluated respectively are good. I understand that

  From Table 4, it can be seen that if the blending of LLDPE and LDPE of the first layer 4 and the second layer 5 is not performed, the bending rigidity and impact resistance tend to decrease, including workability. It turns out that the effect by this invention is acquired and favorable workability is acquired by performing the blend ratio of the thermoplastic resin of each layer in the range of 80: 20-90: 10 here.

  From Table 5, when AB agent is not added to the 1st layer 4, the tendency for slipperiness and blocking resistance to fall is seen. On the other hand, even if the addition amount of AB agent is excessive, it turns out that favorable slipperiness is not obtained. Further, it can be seen that the slipping property tends to be lowered when the lubricant is not added at all or when it is added excessively. Here, it is understood that the AB agent is in the range of 10000 ppm to 35000 ppm, and if the lubricant is also contained at about 100 ppm, the effect according to the present invention can be obtained and good slipperiness can be ensured. Further, at this time, it can be seen that there is no problem whether the AB agent is an organic particle or an inorganic particle.

DESCRIPTION OF SYMBOLS 1 ... Laminated film 2 ... Front surface 3 ... Back surface 4 ... 1st layer 5 ... 2nd layer 6 ... Packaging material 7 ... Base material layer 8 ... Functional layer 12 ... Standing pouch 13 ... Pouch surface 14 ... Pouch back surface 16 ... Extraction nozzle 17 ... opening cut line 18 ... opening knob 19 ... half cut line 20 ... bottom tape 21 ... bent part ridge line 22 ... side seal part 23 ... bottom seal part 24 ... dispensing nozzle seal part 25 ... dispensing nozzle tip seal part 26 ... Embossed part 241 ... Jig for organic lubricant surface extraction 242 ... Organic solvent

Claims (10)

A laminated film comprising a thermoplastic resin as a main resin, having at least a first layer and a second layer,
The first layer contains a fatty acid amide as an organic lubricant,
Contains at least one of organic particles or inorganic particles,
The average crystallinity of the first layer is 30% to 50%, and the thickness of the first layer is 5 μm to 30 μm,
The average crystallinity of the second layer is 40% or more and 60% or less, which is higher than the average crystallinity of the first layer, and the thickness of the second layer is 30 μm or more and 100 μm or less. Laminated film.   The laminated film is characterized in that the average crystallinity of the first layer and the second layer is 35% to 70% even after a heating step of 30 ° C to 80 ° C. Item 2. The laminated film according to Item 1. The thermoplastic resin is mainly composed of polyethylene or a derivative thereof,
The average density of the first layer is 0.910 g / cm ³ or more and 0.930 g / cm ³ or less,
The average density of the second layer is 0.920 g / cm ³ or more ~0.940g / cm ³ or less, and, laminated according to claim 1 or 2, characterized in that higher than the average density of the first layer the film.   The first layer and the second layer are both formed by mixing linear low density polyethylene (LLDPE) and low density polyethylene (LDPE) in a weight ratio of 99: 1 to 70:30. The laminated film according to claim 1, wherein the laminated film is a film.   5. The fatty acid amide contained in the first layer has a molecular weight of 50 to 350 and the content of the first layer is 30 ppm to 150 ppm. The laminated film according to item.   2. The organic particles or inorganic particles contained in the first layer have an average particle diameter of 3 μm or more and 15 μm or less, and the content of the first layer is 6000 ppm or more and 50000 ppm or less. The laminated film according to any one of -5.   The surface of said 1st layer has a convex-shaped part, and arithmetic mean roughness Ra (JISB0601-2001) of the said surface is 0.5 micrometer or more and 2.0 micrometers or less, It is characterized by the above-mentioned. The laminated film according to any one of the above. 8. The laminated film according to claim 1, wherein the amount of the organic lubricant present on the surface of the first layer is 5 mg / m ² or less.   A packaging material, wherein a base material layer is laminated on the laminated film according to any one of claims 1 to 8.   A package using the packaging material according to claim 9.